GardenAnnual Flower · 15 varieties
Sweet alyssum
Lobularia maritima
Brassicaceae — the same plant family as cabbage, radish, broccoli, cauliflower and 12 more here. Relatives share pests and diseases, which is why rotation plans group by family.
Sweet alyssum (Lobularia maritima) is an annual flower. It wants full sun and pH 5.5–7 soil, with about 1 in of water weekly. It matures in about 42–56 days from sowing, or 7–21 days from setting out a transplant. Watch for aphids and downy mildew. Below: its full sourced profile from 9 extension sources, plus a planting calendar timed to your frost dates.
Typical dates for zone 6b — set your zone or ZIP for yours. This calendar assumes the crop is started indoors. Timing is a guide from the crop's sourced growth stages; confirm with your local frost dates and extension before you sow.
What we will not put a number on
We do not give a feeding rate for this crop, and that is deliberate rather than a gap. The figures published by extension services are pounds of nitrogen per acre for a production field — they do not convert safely to a raised bed or a pot without knowing your soil test and your fertilizer's analysis, and guessing errs toward burning roots. It is also why every chart you find online disagrees with the next one.
We give watering as a depth per week rather than gallons per plant, because that is how it is actually measured and how the published figures are written. A gallons-per-plant number depends on your spacing, your soil and whether the plant is in a pot — so it would look more precise than it is.
Site & soil
- Sun
- Full sun
- Soil pH
- 5.5–7
- Soil texture
- Clay, Loam, Sandy, Well drained
- Frost tolerance
- Hardy
No published figure for the temperature frost starts to hurt it. We looked — where a number is missing here it is missing from the research, not skipped. The crop’s frost and heat tolerance above still applies.
The plant
- Mature height
- 3–12 in
- Mature spread
- 0.5–4 ft
- Growth rate
- Moderateest
- Spacing in row
- 6 in
- Between rows
- 6 inest
- Planting depth
- 0.125 in
- Container size
- 0.25–0.5 gal — low end is the minimum, high end is betterest
- Support
- Self-supporting
- Grown from
- Direct sow, Transplant, Cutting
Water & feeding
- Water needs
- Moderate
- Water per week
- 1 in/wkest
- Critical water
- Establishmentest
- Feeding
- Low
Timing & fruiting
- Days to maturity
- 42–56 days from seed · 7–21 days from transplantest
- Survives in the ground down to
- 28 °F
Planted again for autumn
- Set plants out by
- mid Oct typical · zone 6b
7 days to maturity from setting a plant out — that is what our sources measure for this crop, so this is a date for planting out and not a sowing date, counted back from the first frost above. Not published for anywhere in particular: it is your own frost date and this crop's own figure, which is why it works wherever you are. A days-to-maturity figure is a catalog number for a good season rather than a promise, and a cold month moves it.
Edible parts per source: flower.
Compiled from the extensions cited below. Which ones actually show up depends on your region — your extension's local list is the last word.
Its flowers feed hoverflies, and hoverfly larvae eat aphids. Commercial lettuce growers interplant it for that exact job.
Companion pairings from university extensions; badge = how strong the evidence is.
Different parts differ — the edible part is the flower; the notes below flag other parts or preparations.
PeopleNon toxic
PetsNon toxic to dogs, Non toxic to cats, Non toxic to horses
Recorded exactly as the source states it — not medical or veterinary advice. If a person or animal may have eaten a toxic part, call Poison Control (1-800-222-1222) or your vet / the ASPCA line (888-426-4435).
| Variety | Type | Habit | Days | Color | What it is known for |
|---|---|---|---|---|---|
| Carpet of Snow Heirloom | Heirloom | Spreading | 42 | White | Clemson Cooperative Extension, Home & Garden Information Center records this asdraws bees and butterflies · drops seed and comes back on its own · gets by on less water · deer usually leave it alone · smells good · happy in a pot · the flowers are edible |
| Clear Crystal Purple Shades | Clear Crystal | 7–21 | Purple | Clemson Cooperative Extension, Home & Garden Information Center records this asdraws bees and butterflies · drops seed and comes back on its own · gets by on less water · deer usually leave it alone · smells good · happy in a pot · the flowers are edible | |
| Clear Crystal White | Clear Crystal | 7–21 | White | Swallowtail Garden Seeds describes this astakes the heat · takes the cold | |
| Easter Bonnet Deep Pink | Easter Bonnet | 35 | Pink | ||
| Easter Bonnet Mix | Easter Bonnet | 35 | Bicolor | Clemson Cooperative Extension, Home & Garden Information Center records this asdraws bees and butterflies · drops seed and comes back on its own · gets by on less water · deer usually leave it alone · smells good · happy in a pot · the flowers are edible | |
| Easter Bonnet Violet | Easter Bonnet | 35 | Purple | ||
| New Carpet of Snow | Carpet | 7–21 | White | Clemson Cooperative Extension, Home & Garden Information Center records this asdraws bees and butterflies · drops seed and comes back on its own · gets by on less water · deer usually leave it alone · smells good · happy in a pot · the flowers are edible | |
| Oriental Night | 7–21 | Clemson Cooperative Extension, Home & Garden Information Center records this asdraws bees and butterflies · drops seed and comes back on its own · gets by on less water · deer usually leave it alone · smells good · happy in a pot · the flowers are edible | |||
| Rosie O'Day Heirloom | Compact | 63–77 | Pink | All-America Selections describes this asan All-America Selections winner | |
| Royal Carpet Heirloom | Heirloom | 56–63 | Purple, Red | Clemson Cooperative Extension, Home & Garden Information Center records this asdraws bees and butterflies · drops seed and comes back on its own · gets by on less water · deer usually leave it alone · smells good · happy in a pot · the flowers are edible | |
| Snow Crystals | Tetraploid | 7–21 | White | Missouri Botanical Garden Plant Finder describes this astakes the heat | |
| Snow Princess F1 | Hybrid | 7–21 | White | Proven Winners describes this astakes the heat · takes the cold · happy in a pot · draws bees and butterflies · no seeds | |
| Tiny Tim Heirloom | Heirloom | 7–21 | Clemson Cooperative Extension, Home & Garden Information Center records this asdraws bees and butterflies · drops seed and comes back on its own · gets by on less water · deer usually leave it alone · smells good · happy in a pot · the flowers are edible | ||
| Wonderland Deep Purple | Wonderland | 63–77 | Purple | Swallowtail Garden Seeds describes this assmall enough for a pot | |
| Wonderland White | Wonderland | 63–77 | White | True Leaf Market describes this assmall enough for a pot · happy in a pot |
- Clemson Cooperative Extension, Home & Garden Information Center
- Iowa State University Extension and Outreach, Small Farm Sustainability
- Missouri Botanical Garden
- Montana State University Extension
- NC State Extension
- South Dakota State University Extension
- University of Florida IFAS Extension, Gardening Solutions
- University of Illinois Extension
- University of Wisconsin-Madison Division of Extension
We compile bare facts from these university-extension and horticultural sources, never copied prose. 13 of the 19 values on this page carry a citation. The rest are marked est; hover one and it says why — either nobody publishes a figure we could point at, or a person set it and attached no source. Figures vary with climate and seed source; confirm with your local extension before you buy.
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